linux/drivers/video/backlight/hp680_bl.c

190 lines
4.2 KiB
C

/*
* Backlight Driver for HP Jornada 680
*
* Copyright (c) 2005 Andriy Skulysh
*
* Based on Sharp's Corgi Backlight Driver
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/spinlock.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <asm/cpu/dac.h>
#include <asm/hp6xx/hp6xx.h>
#include <asm/hd64461/hd64461.h>
#define HP680_MAX_INTENSITY 255
#define HP680_DEFAULT_INTENSITY 10
static int hp680bl_powermode = FB_BLANK_UNBLANK;
static int current_intensity = 0;
static spinlock_t bl_lock = SPIN_LOCK_UNLOCKED;
static void hp680bl_send_intensity(int intensity)
{
unsigned long flags;
if (hp680bl_powermode != FB_BLANK_UNBLANK)
intensity = 0;
spin_lock_irqsave(&bl_lock, flags);
sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
spin_unlock_irqrestore(&bl_lock, flags);
}
static void hp680bl_blank(int blank)
{
u16 v;
switch(blank) {
case FB_BLANK_NORMAL:
case FB_BLANK_VSYNC_SUSPEND:
case FB_BLANK_HSYNC_SUSPEND:
case FB_BLANK_POWERDOWN:
if (hp680bl_powermode == FB_BLANK_UNBLANK) {
hp680bl_send_intensity(0);
hp680bl_powermode = blank;
sh_dac_disable(DAC_LCD_BRIGHTNESS);
v = inw(HD64461_GPBDR);
v |= HD64461_GPBDR_LCDOFF;
outw(v, HD64461_GPBDR);
}
break;
case FB_BLANK_UNBLANK:
if (hp680bl_powermode != FB_BLANK_UNBLANK) {
sh_dac_enable(DAC_LCD_BRIGHTNESS);
v = inw(HD64461_GPBDR);
v &= ~HD64461_GPBDR_LCDOFF;
outw(v, HD64461_GPBDR);
hp680bl_powermode = blank;
hp680bl_send_intensity(current_intensity);
}
break;
}
}
#ifdef CONFIG_PM
static int hp680bl_suspend(struct device *dev, pm_message_t state, u32 level)
{
if (level == SUSPEND_POWER_DOWN)
hp680bl_blank(FB_BLANK_POWERDOWN);
return 0;
}
static int hp680bl_resume(struct device *dev, u32 level)
{
if (level == RESUME_POWER_ON)
hp680bl_blank(FB_BLANK_UNBLANK);
return 0;
}
#else
#define hp680bl_suspend NULL
#define hp680bl_resume NULL
#endif
static int hp680bl_set_power(struct backlight_device *bd, int state)
{
hp680bl_blank(state);
return 0;
}
static int hp680bl_get_power(struct backlight_device *bd)
{
return hp680bl_powermode;
}
static int hp680bl_set_intensity(struct backlight_device *bd, int intensity)
{
if (intensity > HP680_MAX_INTENSITY)
intensity = HP680_MAX_INTENSITY;
hp680bl_send_intensity(intensity);
current_intensity = intensity;
return 0;
}
static int hp680bl_get_intensity(struct backlight_device *bd)
{
return current_intensity;
}
static struct backlight_properties hp680bl_data = {
.owner = THIS_MODULE,
.get_power = hp680bl_get_power,
.set_power = hp680bl_set_power,
.max_brightness = HP680_MAX_INTENSITY,
.get_brightness = hp680bl_get_intensity,
.set_brightness = hp680bl_set_intensity,
};
static struct backlight_device *hp680_backlight_device;
static int __init hp680bl_probe(struct device *dev)
{
hp680_backlight_device = backlight_device_register ("hp680-bl",
NULL, &hp680bl_data);
if (IS_ERR (hp680_backlight_device))
return PTR_ERR (hp680_backlight_device);
hp680bl_set_intensity(NULL, HP680_DEFAULT_INTENSITY);
return 0;
}
static int hp680bl_remove(struct device *dev)
{
backlight_device_unregister(hp680_backlight_device);
return 0;
}
static struct device_driver hp680bl_driver = {
.name = "hp680-bl",
.bus = &platform_bus_type,
.probe = hp680bl_probe,
.remove = hp680bl_remove,
.suspend = hp680bl_suspend,
.resume = hp680bl_resume,
};
static struct platform_device hp680bl_device = {
.name = "hp680-bl",
.id = -1,
};
static int __init hp680bl_init(void)
{
int ret;
ret=driver_register(&hp680bl_driver);
if (!ret) {
ret = platform_device_register(&hp680bl_device);
if (ret)
driver_unregister(&hp680bl_driver);
}
return ret;
}
static void __exit hp680bl_exit(void)
{
platform_device_unregister(&hp680bl_device);
driver_unregister(&hp680bl_driver);
}
module_init(hp680bl_init);
module_exit(hp680bl_exit);
MODULE_AUTHOR("Andriy Skulysh <askulysh@image.kiev.ua>");
MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");
MODULE_LICENSE("GPL");